close all;
clear all;
clc;

%define grid
Sx=1;  %physical size along x
Sy=1;  %physical size along y
Nx=20; %number of cells along x
Ny=20; %number of cells along x


% grid arrays
dx = Sx/Nx;
xa=[0:Nx-1]*dx;
xa = xa - mean(xa);

dy = Sy/Ny;
ya=[0:Ny-1]*dy;
ya = ya - mean(ya);


% create circule
rx = 0.35;
ry = 0.45;
[Y,X] = meshgrid(ya,xa);

A = ((X/rx).^2 + (Y/ry).^2) <= 1;

% fill read values
er1 = 1.0;
er2 = 2.4;
A= er1*(1-A) + er2*A;
A;


A'


